Active central nervous system (CNS) metastases. Patients with known central nervous system (CNS) metastases are not eligible; Note: brain imaging is not an eligibility requirement Central nervous system (CNS) metastases . Known central nervous system (CNS) disease, except for treated asymptomatic CNS metastases Symptomatic central nervous system (CNS) metastases or primary CNS lymphoma Known central nervous system (CNS) disease, except for treated asymptomatic CNS metastases Primary central nervous system (CNS) malignancy or CNS metastases. Known central nervous system (CNS) disease, except for treated asymptomatic CNS metastases Central nervous system (CNS) metastases may be permitted but must be treated and neurologically stable Active central nervous system metastases, as indicated by clinical symptoms, cerebral edema, and/or progressive growth (patients with history of central nervous system [CNS] metastases or spinal cord compression are eligible if they are clinically stable for at least weeks before first dose of investigational product and do not require high-dose steroid treatment). Central nervous system (CNS) metastases (brain or leptomeningeal) Active central nervous system (CNS) or leptomeningeal metastasis (brain metastases) Uncontrolled central nervous system (CNS) metastases (previously treated with radiation and off steroids is acceptable) Central nervous system (CNS) metastases or seizure disorder Patients with known leptomeningeal or brain metastases; imaging or spinal fluid analysis to exclude central nervous system (CNS) involvement is not required, unless there is clinical suspicion by the treating investigator Patients with active central nervous system (CNS) disease or history of brain metastases are excluded from study Participants with primary central nervous system (CNS) tumors, or with CNS metastases as the only site of active disease (Participants with controlled brain metastases; however, will be allowed to enroll) GENERAL: Known primary central nervous system (CNS) malignancy or symptomatic CNS metastases. History or evidence of central nervous system (CNS) metastases (patients with pretreated metastases are eligible under certain conditions) Symptomatic brain or central nervous system (CNS) metastases; previously treated and stable CNS disease is allowed Active central nervous system (CNS) metastases and CNS metastases as the only sites of disease Active central nervous system (CNS) metastases. Central nervous system (CNS) metastases: patients with known central nervous system metastases are excluded unless treated surgically or with radiotherapy and stable with no recurrent lesions for at least months from the start of protocol therapy Patients with active central nervous system (CNS) disease or history of brain metastases are excluded from study Patients with active central nervous system (CNS) disease or history of brain metastases are excluded from study Active uncontrolled central nervous system (CNS) metastases Participant has known history or inflammatory bowel disease, pneumonitis, or known uncontrolled metastases to the central nervous system (CNS) (with certain exceptions). Uncontrolled central nervous system (CNS) metastases (i.e. known CNS lesions that are radiographically unstable, symptomatic and/or requiring escalating doses of corticosteroids) Untreated central nervous system metastases; patients with a history of brain metastases must have had no central nervous system (CNS)-directed therapy within the past days and radiological assessment within days of study entry demonstrating a lack of progressive CNS disease Any history of central nervous system (CNS) metastases that is not adequately treated with surgery or SABR > days prior Distant metastatic disease including central nervous system (CNS) or leptomeningeal metastases is not allowed Patients with central nervous system (CNS) metastases who are neurologically unstable Patients with active central nervous system (CNS) disease or history of brain metastases are excluded from study Patients diagnosed with primary central nervous system (CNS) or with CNS metastases/involvement, at any time during the disease course, are excluded from the study. History of clinically manifested central nervous system (CNS) metastases, except if brain metastases have been treated, are stable and are asymptomatic Patient has central nervous system (CNS) metastases or seizure disorder Active central nervous system (CNS) malignant disease in subjects with a history of CNS malignancy. Subjects with stable, prior or currently treated brain metastases are allowed. Primary central nervous system (CNS) tumors or solid tumors with CNS metastases as the only site of active disease Patients may have central nervous system (CNS) metastases which have been treated and are radiographically stable for at least weeks Active central nervous system (CNS) malignant disease in subjects with a history of CNS malignancy. Subjects with stable, prior, or currently treated brain metastases are allowed. Evidence of central nervous system (CNS) metastases Evidence of clinically significant central nervous system (CNS) metastases or symptomatic CNS metastases within days prior to dosing Known central nervous system (CNS) metastases requiring treatment, such as surgery, radiation or steroids Known cerebral metastases, central nervous system (CNS) or epidural tumor Central nervous system (CNS) metastases or seizure disorder Known central nervous system (CNS) metastases Central nervous system (CNS) metastases which do not meet the criteria outlined in the inclusion criteria Patients with active central nervous system (CNS) disease, defined as brain or meningeal metastases that are not in complete remission Presence of central nervous system (CNS) metastases Active or history of central nervous system (CNS) metastases Patients diagnosed with primary central nervous system (CNS) or with CNS metastases or involvement, at any time during the disease course, are excluded from the study. Presence of known, active central nervous system (CNS) metastases Any history of central nervous system (CNS) metastases that is not adequately treated (surgery or radiation) > days prior to registration Central nervous system (CNS) metastases or a primary CNS tumor that is associated with progressive neurological symptoms. Patients with known primary central nervous system (CNS) malignancy or symptomatic CNS metastases are excluded Central nervous system (CNS) metastases or seizure disorder Central nervous system (CNS) metastases which do not meet the criteria outlined in inclusion criteria Known primary central nervous system (CNS) malignancy or symptomatic CNS metastases Patients must not have known active central nervous system (CNS) metastases; patients with known central nervous system metastases are excluded unless treated surgically or with radiotherapy, and stable with no recurrent lesions for at least months Distant metastatic disease including central nervous system (CNS) or leptomeningeal metastases is not allowed Uncontrolled central nervous system metastases; treated, non-progressing central nervous system (CNS) disease (documented by brain magnetic resonance imaging [MRI]) off corticosteroids for at least month are eligible Patients with central nervous system (CNS) metastases or a history of CNS metastases are ineligible Patients with active central nervous system (CNS) metastases Known central nervous system (CNS) metastases with active symptoms, or requiring anticonvulsive medications, or steroids Patients with known central nervous system (CNS) metastases must have stable disease off steroids after treatment with surgery or radiation therapy No brain or central nervous system (CNS) metastases Active Central nervous system (CNS) metastases Presence of or known history of brain/central nervous system (CNS) tumor or metastases At the time of Day of the study, subjects with central nervous system (CNS) metastases must have been treated and must be asymptomatic Known primary central nervous system (CNS) malignancy or symptomatic CNS metastases, except ATRT Patients are ineligible if they have any history of central nervous system (CNS) metastases Individuals with known central nervous system (CNS) metastases, unless metastases are treated and stable and the individual does not require systemic steroids Known primary central nervous system (CNS) malignancy or symptomatic CNS metastases Subject has uncontrolled metastases to the central nervous system (CNS). Patients with active central nervous system (CNS) disease or history of brain metastases (mets) are excluded from study Active central nervous system (CNS) metastases requiring treatment Primary central nervous system (CNS) malignancy or active metastases within years Active central nervous system (CNS) metastases Subjects with active central nervous system (CNS) metastases are excluded Phase b: History or evidence of central nervous system (CNS) metastases Central nervous system (CNS) metastases or seizure disorder Subjects with active central nervous system (CNS) metastases causing clinical symptoms or metastases that require therapeutic intervention are excluded Active central nervous system (CNS) metastases. History of central nervous system (CNS) metastases unless previously treated and stable for > weeks prior to study initiation Uncontrolled central nervous system (CNS) metastases, meningeal carcinomatosis, malignant seizures, or a disease that either causes or threatens neurologic compromise (e.g., unstable vertebral metastases). Patients with central nervous system (CNS) tumors or known brain metastases Any history of or current central nervous system (CNS) metastases. Baseline imaging of the brain is required within days prior to randomization Prior or concurrent central nervous system (CNS) metastases Central nervous system (CNS) metastases may be permitted but must be treated and neurologically stable Central nervous system (CNS) metastases Central nervous system (CNS) disease, including treated brain metastases Central nervous system (CNS) metastases No known central nervous system (CNS) metastases Known history of central nervous system (CNS) metastases Previous radiotherapy for cerebral metastases, central nervous system (CNS) or epidural tumor Patients with known central nervous system (CNS) metastases, unless metastases are treated and stable and the patients do not require systemic steroids Any Central Nervous System (CNS) metastases or history of CNS metastases Known central nervous system (CNS) metastases Central nervous system (CNS) metastases which do not meet the criteria outlined in inclusion criteria Known or suspected brain or other central nervous system (CNS) metastases Active central nervous system (CNS) metastases Symptomatic brain or central nervous system (CNS) metastases; previously treated and stable CNS disease is allowed Patients with central nervous system (CNS) metastases are eligible (as long as projected survival is > months) History or known presence of central nervous system (CNS) metastases Central nervous system (CNS) metastases which do not meet the criteria outlined in the inclusion criteria Active central nervous system disease (CNS) metastases, as indicated by clinical symptoms, cerebral edema or progressive growth Known cerebral metastases, central nervous system (CNS) or epidural tumor Central nervous system (CNS): no recent history (within month) of cerebrovascular accident, transient ischemic attacks, central nervous system or brain metastases Known active central nervous system (CNS) metastases. Patients having Central Nervous System (CNS) metastases. Patients who have had brain metastases surgically removed or irradiated with no residual disease confirmed by imaging are allowed Patients are excluded if they have a history of central nervous system (CNS) metastases Central nervous system (CNS) metastases or seizure disorder Known central nervous system (CNS) or brain metastases. Central nervous system (CNS) metastases which do not meet the criteria outlined in inclusion criteria Known central nervous system (CNS) disease, other than stable, treated brain metastases Subject has symptomatic central nervous system (CNS) metastases or leptomeningeal involvement as assessed through medical history review and physical examination. Subject with prior brain metastases must: Subjects with asymptomatic brain metastases or other central nervous system (CNS) disease at screening/diagnosis are eligible CNS (Central Nervous System) tumors as well as history of brain metastases Known brain tumors or Central nervous system (CNS) metastases Known or suspected central nervous system (CNS) metastases or with the CNS as the only site of active disease (controlled CNS metastases are allowed) Known primary central nervous system (CNS) tumors or brain metastases Known central nervous system (CNS) disease except for treated brain metastases Patients with active central nervous system (CNS) disease or history of brain metastases (mets) are excluded from study Central nervous system (CNS) metastases from lymphoma or small cell lung cancer History of Central nervous system (CNS) or brain metastases No evidence of central nervous system (CNS) metastases Unstable metastases to the central nervous system (CNS) Central nervous system (CNS) lymphoma; active brain or leptomeningeal metastases. Participants with central nervous system (CNS) (e.g., brain or leptomeningeal) metastases. Patients with prior history of primary central nervous system (CNS) cancer or CNS metastases Comorbidities at particular risk (i.e., active central nervous system [CNS], active CNS metastases, hydrocephalus or coagulopathy) Uncontrolled Central Nervous System (CNS) metastases Subjects must not have a history of clinically manifested central nervous system (CNS) metastases. a. Subjects with known or suspected leptomeningeal disease or cord compression are not eligible. Central nervous system (CNS) metastases Evidence of progression of central nervous system (CNS) metastases or symptomatic CNS metastases within days prior to dosing.